Telephone-exchange system.



W. W.-DEAN.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAY 20, I907.

Patented J 51;. 25, 1916.

artan sears PATENT @FFEQE.

IL'LIAM'W; DEAN, oF-ELYiRIaoHIo. AssIGNoR, IBY MESNE AssIGNMEn rs, o TI-IVE GARFORD M NUFACTU IN COMPANY, or ELYRIA, OHIO, A conronar on or OHIO.

Emerson's-EXCHANGE .S'Y'STEM.

To all whom it may concern: n I

Be itknown that I, WILLIA1\[ W. DEAN, citizen of the United States, residing at Elyria, in the county of Lorain and State of Ohio, have invented certain new and useful Improvements in Telephone-Exchange Systems, of which the following is a specification, reference being had therein to the accompanying drawing,

My invention relates to telephone exchangesystems, and has for its objectto provide means wherebythe clearing-out or cutting-otfof connected lines and the control of the connective circuits is effected by certain acts of the calling and called subscriber jointly.

My invention is in its nature generic, and

is intended to be applied eitherto automatic orto manual exchange systems." In both cases its operation is essentially the same, and I shall therefore make broad claims in the present case.

In Patent No. 854,279 of May 21, 1907,

I have described and claimed a specific form of this invention as applied to manual exchange systems only. In the present application therefore, in addition to claiming broadly the principal features irrespective ofthe type of system in which they are incorporated. I shall/specifically claim their embodiment in an automatic connecting circuit.

Broadly stated, my invention contemplatesthemaking of a call by a'telephone subscriber. and. the completion of the connection at the central office, with one other succeeding act required either on the partof the calling or of the called subscriber, before the connection can be taken down or jib cleared out by a subscriber. Of course, a

connection can be .cleared out by an operator at any time, but'my invention relates directly to an automatic clearing-out apparatus controlled bv the subscriber.

My invention is illustrated in the accompanying drawings,wherein the figure is a diagram showing my invention as applied to anautomatic connector circuit having automatic rlngin'g.

A" 'indicates the vertical relay of a Strowger automatic switch "such aS that Patented J an. 25, 1916.

'Application filed May 2 0, 1907. Serial No. 374,754.

shown in the patent to Keith and Erickson, 815,176, granted March 13, 1906. i

C indicates the rotary relay and a and 0 denote the rotary and vertical magnets respectively.

"P denotes the private relay controlling .the side switches shown at s, 5 .9 and 8 B denotes the main battery.

U indicates the spindle, a: and w indicate the wipers carried thereby, while (Z and (l indicatethe contacts. The test wiper t is arranged as shown in the figure.

R denotes the release magnet.

At each subscriber's station there is provided a sender of the usual Strowgertype which may be operated by the subscriber to send a predetermined number of impulses over the line according to the number set up on the dial, this being the ordinary procedure in operating an automatic connecting circuit of this kind, I have indicated this sender by the pair or keys 1) and D.

The relay S is provided with a pair of armature's c and e, the operation of the relay depending on mechanism hereinafter described.

An automatic ringing device consisting of a generator G and an interrupter H is arranged to furnish ringing current which may be projected upon the lines b the 010s ing of the contacts :0 and a through the armatures of the relay J. In series with the relav J is a slow acting relay K provided with a dashpot L which is so ar- .batterv B. the other terminal of such bat:- terv being grounded.

The enumeration of the different parts shown in the figure will be sufficient for a clear understanding of the operationfio'f my inventionas applied to air-automatic connector circuit having automaticringing.

Suppose the subscriber wishes to get into talking communication with another subing these side switches to their second position. The subscriber then repeats the operation, this time sending five vertical impulses and a rotary impulse as before. The five impulses operate. the rotary relay A and its associated magnet a, thereby turning the spindle and its wipers to the fifth contact on the row which connects the two subscribers. The line is then tested in the usual manner and if found busy, the release magnet operates-to restore the switch to its normal position. i If the line is not busy, the calling subscriber presses the button D thereby actuating the vertical relay A the current passing directly fro-1n the battery B through the relay and to ground at the subscribers station. The armature of the relay A pulls up and in doing so closes contact at g which thereupon establishes a circuit through the relays K and J' by the following path: battery, 2, 3, 4, 5', g, 6', 7. 7', 8', J, 9', K,-10, 11', contact 1' which is closed when the spindle 'U is raised, and ground. The relay J pulls up and puts current on the line through the contacts so and-z, the relay J being looked through the contact y. When the called subscriber responds, ground is put on both sides of his line momentarily by his hook switch, and the relay S is actuated through the coil M. v

In case the called subscriber does not answer, the armatures of the relay 'K slowly pull up, taking say fifteen seconds for a full actuation. Before completing its travel the lower armature momentarily closes the contact n, and puts a ground on the relay S which pulls up and looks through its arma-' ture e, the locking circuit. being completed thus: battery, relay. S, e,' 11, 1', ground.

When the relay'K has fully pulled up, de pending upon the arrangement-of the dash-- pot-which may be constructed to operate in any desired time, a shuntis closed around the relay J through the contact m by the following pathz-battery 2, 3,4, 12,'m-, K,'10, 11,'-1, and ground. The relay QJ lets vgo, cutting off the ringingcurrent from the line. V

' The relay S being-locked in the mannerdescribed and the contact being closed through the armature e, the line is now in condition for clearing out whenever the calling subscriber hangs up. When this is done amomentary 'groundfjis'put on each side ofthe line as usual. .The relays A and both pull up and'the release circuit is closed-ate.- The circuit at o" is closed before the contacts at g engage. This actuates the-release magnet R'., the current flowing through the followlng path: battery, e, 13', 14, R, 15, 16, 17', 0, 18 and ground. The release magnet R operates to restore the switch to its.

normal condition.

It will be seen from the above description that after the calling subscriber has sent in the required signals and has set in operation the automatic ringing mechanism, he is then in condition to clear out whether the called subscriber answers or not.

Having thus described my. invention,

what I claim and desire to secure by-Letters Patent is: I

1. In a telephone exchange system,v a calling and a 'called subscribers line and an automatic switch for; interconnecting the same, a release magnet for said switch normally disabled, and means controlled by the removing the disability of said magnet and for rendering it operative for clearingout purposes. i

2. In a telephone exchange system, a calling and a called subscribers line and an automatic switch for interconnecting them, a normally disabled release magnet for the switch,

a relay connected to the interconnecting circuit through said switch so as to be responsive to the act of a called subscriber, and a device responsive to the actof'the calling subscriber for actuating said relay after a predetermined lapseof time only,

said relay when energized acting to render control over the connection. 7

4. In an automatic telephone exchange system, a calling and :1 called subscribers line, means for interconnecting them, anor- .mally disabled means for restoring-the connectmg means tortsanoperatwe condition,

and meansunder the control of the called subscriber for removing the disability of the restoring means, the operating circuit of such removing means extendingfrom the. called substation over both sides of .the

called line to the. removing means and back to the called substation by means of a third conductor. Y

5. -In an automatic telephone exchange system, ascalling and a calledsubscribers 1ine,"n1jeans for interconnecting them,- it norcalled-subscriber in answering a call for to deprive the called subscriber of further mallydisabledmeans for restoring the con nectrng means to ItS inoperativecondition, and a relay under the control'of the called subscriber, such relay adapted by its operation 'to close one breakin the energizing circuit of the restoring means-when the called subscriber responds to the call.

6. In a telephone exchange system, a calling and a called subscriber's line, an auto matic switch for interconnecting them, a release magnet for such switch, and a relay under the'control of the called subscriber, such relay adapted by its operation to close one'break in the energizing circuit of the release magnet when the called subscriber responds. I

7. In ,a, telephoneexchange system, a calling and a called subscriber's line. an automatic switch for interconnecting them, a release magnet for such switch, a relay under the control of the called subscriber, such relay adapted by its operation to close one break in the energizing circuit of the release magnet when the called subscriber responds, and means under the control of the calling subscriber for closing a second break in the release magnet energizing circuit and thus completing the same.

R. In a telephone exchange system, a calling and a called subscribers line. an automatic switch for interconnecting them, a release magnet for such switch, a relay under the control of the called subscriber, such relay adapted by its operation to close one break in the energizing circuit of the release magnet, such operation serving to lock the relay against further operation during the continuance of the same connection, and 11121115 under the control of the calling subscriber for closing a second break in the release magnet energizing circuit and thus completing the same.

9. In a telephone exchange system, a calling and a called subscribers line. an automatic switch for interconnecting them, a release magnet for such switch, a relay under the control of the called subscriber, such relay adapted by its operation to close one br ak in the energizing circuit of the release magnet, the operating circuit of such relay extending from the called substation over both sides ofthe called line in parallel to such relay and back to the called substation by means of a third conductor, and means under the control of the calling subscriber for closing a second break in the release magnet energizing circuit and thus completing the same.

10. In a telephone exchange system, a calling and a called subscribers line. an automatic switch for interconnecting them, a release magnet for such switch. a relay under the control of the called subscriber, such relay adapted by its operation to close one breakin the energizing circuit of the release relay against further operation during the continuance of the same connection, and

means under the control of the calling subscriber operative only after a predetermii'ied interval for closing such break in the release magnet energizing circuit.

12. In a telephone exchange system, a calling and a called subscribers line, an automatic switch for interconnecting them, a release magnet for such switch, a relay under the control of the called subscriber, such relay adapted by its operation to close one break in the energizing circuit of the re lease magnet. the operating circuit of such relay extending from the called substation over both sidesof the called line in parallel to such relay and back to the called substation by means of a third conductor, and means under the control of the calling subscriber operative only after a predetermined interval for closing such break in the release magnet energizing circuit.

13. In a telephone exchange system, a call ing and a called subscribers line, an automatic switch for interconnecting them, a release magnet for such switch, a relay under the control of the called subscriber, such relay adapted by its operatio. to close one break in the energizing circu of the release magnet when the called suescriber responds. means under the control e th calling subscriber operative only after a predetermined interval for closing such break in the release magnet energizing circuit, and means under the control of the callin sub-T scriber for closing a second break in tierelease magnet energizing circuit and thus completing the same.

14. In a telephone exchange system, a calling and a called subscribers line, an automatic switch for interconnecting them,

a release magnet for such switch, a relay under the control ofthe called subscriber, such relay adapted by its operation to close one break in the energizing circuit of the release magnet, such operation serving to lock the relay against further operation during the continuance of the same connection, means ,under the'control of the calling subscriber operative only after a predetermined inter val for closing such break in the release magnet energizing circuit, arid means under the control of the calling subscriber for closing a second break in the release magnet energizing circuit and thus completing the same.

15. In a telephone exchange system, a calling and a called subscribers line, an autos matic switch for interconnecting them, a release magnet for such switch, a relay under the control of the called subscriber, such relay adapted by its operation to close. one' break in the energizing circuitof the re lease magnet, the operating circuit of such relay extending from the called substation over both sides of the called line in parallel to such relay andback-t'o the called substation by means of a third conductor, means under'the control-of the calling subscriber Qenergizing circuit and thus completing the :same.

16. In a telephone system, the combination of a central station, a plurality of telephone lines leading into said central station,

substations onsaid lines, one of said lines being a called line and another a calling line, connecting mechanism, a normally disabled' means for restoring the connecting means to its inoperatlve cond1t10n and means under the control of the called subscriber for removing the disability of the restoring means, such removal serving to-deprive the system, a calling and a called subscribers line,-means for interconnecting them, a nor mally disabled means for restoring the'connecting means toits inoperative condition, and a relay under the control of the called subscriber, such relay adapted by its operation to close one break in the energizing circuit of therestoring means, the operating circuit of such relay extending from the called subscriber over both sides of. the called line in parallelto such relay and back to the called substation by means of a third conductor. a

In testimony whereof I afiix my signature in presence oftWo Witnesses.

' \VILLIAM WV. DEAN, Witnesses M. E. MIzEn, S. A. BEYLAnD. 

